This invention relates generally to the detection of hazardous material, and, more particularly to the application and sensing of sensitizing agents for early detection of potentially hazardous material associated with mail pieces or the delivery of other objects.
Recently there has been increased awareness of the potential for large-scale introduction of hazardous materials, that is, either explosives or biological organisms to create chaos or to harm an intended set of victims. Awareness to detection of explosives has led to development of reagents that can be used to detect the presence of nitroaromatics, organic nitrates, nitramines, inorganic nitrates, chlorates and bromates based explosives (see U.S. Pat. No. 5,480,612, “Kits for Detecting Explosives”, issued to Y. Margalit on Jan. 2, 1996).
Bacterial agents, such as Bacillus anthracis and Closdistrium botilinum, can be used as biological hazardous materials. Detection methods for bacterial agents have been typically time-consuming using techniques such as florescent antibody staining (FAST) and enzyme linked immunoassay (ELISA). Detection systems have been recently disclosed that involve labeling antibodies with a detectable label where the detectable label utilizes fluorescence, chemiluminescence or chromatic change (see B. L. Mangold et al., international publication WO 01/83561 A2 for International Application No. PCT/US01/13648).
Detection methods have also been recently disclosed in the which the sensor is a polymer which has an alterable property, such as fluorescence or electrical conductivity, and the property is altered by a means of association of the polymer with a moiety including a property quenching element, a tethering element and a ligand or recognition element (see L. Chen et al., international publication WO00/66790 for International Application No. PCT/US00/12423 and see D. G. Whitten et al., international publication WO01/85997 A1 for International Application No. PCT/US01/14702). In this latter method, upon exposure to the biological agent, the agent can bind to the ligand or recognition element causing the moiety (with the bound biological agent) to separate from the polymer thereby un-quenching the alterable property. (The recognition element can be one of, but not restricted to, a chemical ligand, an antibody or antibody fragment, a peptide nucleic acid, or a protein.) Measurement of the alterable property results in detection of the biological agent.
A popular delivery method among the many delivery methods that terrorists or other criminals utilize to deliver such hazardous materials is to utilize the mail to deliver the hazardous material. In so doing, not only is damage incurred by the intended victims, but also by any set of potential victims that may be in a position of handling such objects as the mail during the delivery or distribution process.
As described above, there is currently technology available to law enforcement organizations to detect the presence of both explosive and biological threats. Test kits utilizing the above described materials generally require the gathering of a sample and analyzing offline. To date, however, there is a lack of systems for early detection of such hazardous material in the early phases of mail handling or processing. Systems currently in place do not deal with detection prior to entering into the formal distribution process. Thus, all along the distribution process potential non-intended victims are being subjected to hazardous material carried by, for example, letter or package mail.
There is a need for a system and method for early detection of such hazardous material in the early phases of mail handling or processing. There is also a need for a system and method for early detection of such hazardous material that can be performed while the mail is being processed.